The present invention relates to an optically active dihydropyridine derivative, a pharmacologically acceptable salt thereof having superior blood pressure lowering action, cardiac protective action, anti-arteriosclerotic action and kidney disorder ameliorative action, and a therapeutic agent or preventive agent (to delay or prevent the onset) comprising the same for hypertension, heart diseases, arteriosclerosis and kidney disorders.
Since (±)-2-amino-1,4-dihydro-6-methyl-4-(3-nitrophenyl)-3,5-pyridinedicarboxylic acid 3-(1-diphenylmethylazetidin-3-yl) ester 5-isopropyl ester (hereinafter referred to as Compound (I)), a dihydropyridine calcium antagonist, has pharmacological activities such as calcium antagonistic action, antihypertensive action, vascular dilatory action, cardiac protective action, anti-arteriosclerotic action, diuretic action, renal disorder inhibitory action and lipid peroxide formation inhibitory action and it also has a low level of toxicity, it is known to be useful as a pharmaceutical for treating diseases of the circulatory system such as hypertension, angina pectoris and arteriosclerosis (refer to, for example, Japanese Examined Patent Publication (Kokoku) No. Hei 3-31715 (specification of U.S. Pat. No. 4,772,596)).